I have a 700 watt kicker amp bolted to the floor. It made too much heat in there, so I made a sub-floor, that covers the well, all but about an inch at the rear of the well. I mounted a large fan from a server in the front right corner of the sub-floor, to circulate air. I used a speaker grill from an 8" sub, to protect the fan. It now stays very cool, and I have a clear floor to carry whatever in the trunk. Lost a little height, but the trunk is still quite functional.
The spare still fits in the original location, but I need to reroute the cables, and finish off the mounting for the floor. I put in a relay, that is switched by the head unit, so the fan only runs when the tunes are turned on.
All Kicker speakers, 2 - 6.5" components in the doors, tweeters mounted in the outer ac vents, 4 - 3.5" in the headrests, 2 - 8" subs in a JL stealthbox. Top down, the car wont go fast enough to make the sound less than excellent! Pioneer head unit, with a 250 gig hard drive for music storage, long trips, wife at home, great tunes, big smiles!